Purpose: To compare directly the two most widely used methods of functional magnetic resonance (MR) imaging--dynamic contrast material-enhanced MR imaging and blood oxygenation level-dependent (BOLD) MR imaging.
Materials and methods: Five healthy volunteers underwent dynamic contrast-enhanced and BOLD MR imaging with a conventional 1.5-T MR unit during visual stimulation and a dark control state. BOLD studies were performed with a gradient-echo sequence, and dynamic MR imaging was performed with an echo-shifted gradient-echo sequence after intravenous administration of a bolus of gadopentetate dimeglumine.
Results: A significantly greater percentage signal change was found with dynamic MR imaging than with the BOLD technique. The extent of area activated was also significantly greater.
Conclusion: With standard clinical imagers and these gradient-echo-based techniques, greater percentage activation and area of activation can be achieved with dynamic MR imaging than with BOLD MR imaging.